1. Technical Field of the Invention
The present invention relates to a protective device for electrically operated equipment. More particularly, the present invention relates to protective device for electrically operated equipment, particularly equipment of a portable nature, which is fed from a power line and through a power cord connection.
2. Description of the Prior Art
Protective devices of the type to which the present invention is directed are those intended to protect equipment which can be used in the workplace or in households in damp areas, especially bathrooms. Additional uses for such protective devices are, for example, uses in connection with immersion pumps, air-bubble massage equipment (e.g., DE 26 31 785), kitchen equipment, hair dries (e.g., European Patent Application No. 1831), forced-air heaters or irradiation lamps, and the protection of such devices against damage by water and to further protect their users against receiving an electrical shock.
Such protective devices can either be installed in the electrical equipment itself, as shown in European Patent No. 88,390 (which corresponds to U.S. Pat. No. 4,589,047), in the plug of its power cord, as shown in European Patent Application No. 1831 and DE 26 31 785, or in an intermediate plug, as described in DE 25 39 279. In the latter case, it is possible to introduce the protection into an item without changing the design of the equipment.
As opposed to protective devices which use holding-current relays to disconnect the line current in the event of danger, and where is it therefore possible to switch the power on again as soon as the disturbance has been eliminated, the protective devices of the type known to the prior art, to which the present invention is directed, require that once a dangerous incident has occurred, i.e., the firing circuit has responded and has thrown the protective switch, that the power cord of the equipment--including the power plug--or at least the intermediate plug, must be replaced.